And as the `Response` can be used frequently to set headers and cookies, **FastAPI** also provides it at `fastapi.Response`.

///

## Custom Headers { #custom-headers }

Keep in mind that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the `X-` prefix</a>.

///

## Cabeçalhos personalizados { #custom-headers }

Tenha em mente que cabeçalhos personalizados proprietários podem ser adicionados <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">usando o prefixo `X-`</a>.

///

## Headers Personalizados { #custom-headers }

Ten en cuenta que los headers propietarios personalizados se pueden agregar <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">usando el prefijo `X-`</a>.

///

## Benutzerdefinierte Header { #custom-headers }

Beachten Sie, dass benutzerdefinierte proprietäre Header <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">mittels des Präfix `X-`</a> hinzugefügt werden können.

///

## Пользовательские HTTP-заголовки { #custom-headers }

Помните, что собственные проприетарные заголовки можно добавлять, <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">используя префикс `X-`</a>.

/// warning | Advertencia

Antes de establecer `convert_underscores` a `False`, ten en cuenta que algunos proxies y servidores HTTP no permiten el uso de headers con guiones bajos.

///

## Headers duplicados { #duplicate-headers }

Es posible recibir headers duplicados. Eso significa, el mismo header con múltiples valores.

Puedes definir esos casos usando una lista en la declaración del tipo.

    )
    assert response.headers["access-control-allow-headers"] == "X-Example"

    # Test standard response
    headers = {"Origin": "https://localhost.tiangolo.com"}
    response = client.get("/", headers=headers)
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Hello World"}
    assert (
        response.headers["access-control-allow-origin"]

    assert response.json() == {"detail": "Not authenticated"}
    assert response.headers["WWW-Authenticate"] == "Bearer"


def test_token(mod: ModuleType):
    client = TestClient(mod.app)
    access_token = get_access_token(scope="me", client=client)
    response = client.get(
        "/users/me", headers={"Authorization": f"Bearer {access_token}"}
    )
    assert response.status_code == 200, response.text

def test_gzip_request(client: TestClient, compress):
    n = 1000
    headers = {}
    body = [1] * n
    data = json.dumps(body).encode()
    if compress:
        data = gzip.compress(data)
        headers["Content-Encoding"] = "gzip"
    headers["Content-Type"] = "application/json"
    response = client.post("/sum", content=data, headers=headers)
    assert response.json() == {"sum": n}

from fastapi import FastAPI
from fastapi.responses import JSONResponse

app = FastAPI()


@app.get("/headers/")
def get_headers():
    content = {"message": "Hello World"}
    headers = {"X-Cat-Dog": "alone in the world", "Content-Language": "en-US"}